Hard to say what the pitch is like but if you're only going for 4-5 S the killer het 1w-40 should work ok and be very under stressed . Need a good strong esc though .It is a little heavier but then you also have a monster motor on future planes (If your 262 ever croaks ) if you go with 6S and wemotech or Het etc. I just bought two motors , the Eflite BL32 for the changesun going into a Nitroplanes F4, but I'm running it on 6S , and the het 1w-40 for 6904 6S in my Het Mig21 (Hope the fan can take it ) .

OK guys, I just got my 12 blade order and here are some photos of the new 12 blade rotor next to the 10 blade rotor. It may not be that obvious in the photos, but the new 12 blade rotor has a little twist at the blade end. The material seems pretty stiff. The shroud seems stiffer than the 10 blade one as well. The 12 blade rotor weights 17.59 grams and the 10 blade weights 13.58 grams. I also tried the Tams 5mm adapter, washer and spinner. The adapter fits the new 12 blade rotor, but the washer and spinner do not. The diameter where the spinner sits is just a hair bigger on the new 12 blade rotor. I would assume you would have the same issue with the Extreme versions of the spinner and adapter. I've written to Tam to see if he plans to produce a spinner and washer for this new rotor and will post my results when I hear back. b/r Mark

OK guys, I just got my 12 blade order and here are some photos of the new 12 blade rotor next to the 10 blade rotor. It may not be that obvious in the photos, but the new 12 blade rotor has a little twist at the blade end. The material seems pretty stiff. The shroud seems stiffer than the 10 blade one as well. The 12 blade rotor weights 17.59 grams and the 10 blade weights 13.58 grams. I also tried the Tams 5mm adapter, washer and spinner. The adapter fits the new 12 blade rotor, but the washer and spinner do not. The diameter where the spinner sits is just a hair bigger on the new 12 blade rotor. I would assume you would have the same issue with the Extreme versions of the spinner and adapter. I've written to Tam to see if he plans to produce a spinner and washer for this new rotor and will post my results when I hear back. b/r Mark

thanks for posting the pics Mark
it looks interesting for sure, so is Tams spinner washer the right O.D. and just the inside shoulder on the rotor needs to be turned down a little? if thats the case then a good option for guys could be to send your new 70/12 rotor and your existing Tam spinner and washer set to him and we can dynamically balance and fit the washer to the rotor for the balance fee of 25 bucks.

Hi guys, i'm new to this (very interesting) thread and i haven't (yet) got my own Vampire However, as soon at the kit version comes back in stock in the UK warehouse i shall be ordering one and can't wait to get testing/flying.

One of my particular interests will be in optimising the propulsion system efficiency so as to get extended flight times (as opposed to maximum thrust) - this means targetting 'modest' thrust levels (say around 1Kgf static thrust - in the model) but hopefully using this new 12 blade fan, since it should, theoretically at least, be more efficient than the 10 blade jobbie.

When you guys with bench test rigs (with thrust meter capability) are able to start some tests on 12 blader - it would be really very handy if you could produce a few test points (Thrust v Watts) for interim power levels (ie in addition to the condition where the system is 'balls-out'). This would enable us to observe how the overall efficiency (grams/watt - g/w) changes with load on the fan - we (should) expect to see much more efficency at lower power levels... the interesting thing will be 'how much more?'.

Such data could then be used to configure/dream-up ways to predictably operate the fan at the more efficient end of the power curve - probably using 5S batteries (for lower heat losses in the motor) but using lower power outputs from the ESC. Such an idea is not without some potential problems though - i'm relatively new to electric power systems, but gather that operating some ESCs (for sustained periods) at less than max power can sometimes lead to ESC over-heating... though i've no experience of this in my operation of propeller aircraft so far. (Would be interested in any thoughts/experience on this)

Anyway - thanks in advance to anyone who'd be prepared to have a go at producing some data...
... a Thrust v. Watts 'curve' would be even better, but perhaps that's a bit much to ask

Rgs to all,

Andy

ps: From observing ALL your data on the CS 10 thread - my hunch/gut-feel/extrapolation is that on:
- A 5S 3300 25C battery
- Operating at around (say) 70~80% max watts
- Using the new 12 blade fan
- We might achieve efficiency levels approaching a g/w of 2.4(ish)
- Which would give us excellent duration, at modest thrust (which is what i'm after)
Ambitious?... Probably... But I'm an optimist!

thanks for posting the pics Mark
it looks interesting for sure, so is Tams spinner washer the right O.D. and just the inside shoulder on the rotor needs to be turned down a little? if thats the case then a good option for guys could be to send your new 70/12 rotor and your existing Tam spinner and washer set to him and we can dynamically balance and fit the washer to the rotor for the balance fee of 25 bucks.

OK, I'm trying to get some measuring here and not be too confusing. You know how both rotors have a raised circular area on the face of the rotor?

On the 10 blade rotor, the diameter of that ridge is 26.56mm. The diameter of the entire rotor face is 29.62mm. The inside diameter of the Tams washer is 26.62mm and the outside diameter for the Tams spinner is 29.51mm.
On the new 12 blade rotor, the diameter of that ridge is 27.86mm. The diameter of the entire rotor face is 30.53mm and the outside diameter of the Change Sun aluminum spinner is 30.53mm. I did these measurements with my small digital caliper so they may be off in the hundreth mm area.

So it looks like the Tams washer doesn't fit that circular ridge, and is also smaller in overall diameter. In addition, the Tams spinner is smaller in diameter than what is needed for the 12 blade rotor. So either Tam has to make a new washer which fits the new Change Sun aluminum spinner or a new washer and spinner. Also, with these pretty small differences, you are also probably right that Tam could just turn down the washer a bit so as to fit the circular ridge on the 12 blade rotor, but then you would have to also use the Tam spinner (which are nice but I'm hoping to be able to use these $2 aluminum spinners from Change Sun). Sorry for the long post.

Hello guys,
I've received my new 12 blades CS version and would like to say the differences about spinners but it seems Alexander has been faster than me
I've ordered two alum spinners to try the second one in my CS10 blades but there's effectively too much clearance and the spinner is not well centered in the CS10. I've also noticed that the new one has a better centering than the CS10 (the centering ring on the new CS12 is more prononced than the CS10 and so when you put the spinner on you really feel a good "clip". The material seems to be different too, and what strike me the most is the shroud, which is completely different (there's 6 stators (or 8 I can't remember and it's in the garage now so I have to check tomorrow), and the cylinder where the motor fits has grooves on it (better for cooling but I guess it won't deform and cause bad centering of the rotor in high stress)
The housing has two external rings too to increase rigidity I think whereas the CS10 didn't, and there's no Change sun engraving like his sister.
Hope you'll understand my english :-)
Have a nice evening everybody
Rdgs
Aurelien